temp gauge in dash reads low, why?

This is a discussion on temp gauge in dash reads low, why? within the Technical / Maintenance forums, part of the General Discussion category; My temp gauge never reads over the 1/4 mark, where straight up is 210, mine reads about 160, but when ...

temp gauge in dash reads low, why?

My temp gauge never reads over the 1/4 mark, where straight up is 210, mine reads about 160, but when I have used a scan tool it shows the temp is warmer, anyone else have this trouble, mine is the only one that I have found that has this.

Re: temp gauge in dash reads low, why?

What temp does the scanner show? On my 99 Tahoe the scanner was reading in line with the T stat at around 192-195 which is the proper temp. The temp guage in the truck would only get up to 160. Replaced the temp sender with the same results. After a little searching I installed an Airtex/Wells # 1T1064 sender and now it reads correct. I think there are a bunch of senders out there that are supposed to work but have the wrong ohm values.

Re: temp gauge in dash reads low, why?

All I know is that mine would always read around 160. I replaced the sender with a new one from napa and it still read 160. I bought the Airtex/Wells sender from Rock Auto and it now reads correctly. Somebody else was having this issue on either this or another forum. It was suggested to use the airtex. I am guessing there are some out there that do have the wrong ohm values but are spec'd for our application. If you change it out let us know what happens.

Re: temp gauge in dash reads low, why?

I had the same issue for a couple years and it was aggravating as hell. Tried new senders but no fix. I took the cover off, pulled the needle, moved it 1/4" and now it reads perfect, checked with datalogger. Reading exactly what pcm is seeing

Re: temp gauge in dash reads low, why?

When I bought my 93 five years ago, the temp gauge didn't register at all. The coolant had never been changed and wasn't reaching the sender because of all the built up goop. I removed the sender and shot some compressed air through the hole. It worked perfectly after that.

Re: temp gauge in dash reads low, why?

The coolant temp sensor by the t-stat is the sensor for the ECU. The sender for the guage is on the drivers side cylinder head. Maybe different for earlier models but for the Vortecs thats where its located.

Re: temp gauge in dash reads low, why?

Sorry, mine is a 97 suburban 350 vortec. I have had 3 thermostats in it, good ones too, new fluid, new water pump, and the sender by the thermostat is new. I will check into the airtex one and see where I can get one, thanks.

Re: temp gauge in dash reads low, why?

Originally Posted by dtmmil

Sorry, mine is a 97 suburban 350 vortec. I have had 3 thermostats in it, good ones too, new fluid, new water pump, and the sender by the thermostat is new. I will check into the airtex one and see where I can get one, thanks.

Sender by the thermostat does not talk to the gauge.

Gauge recieves temp from the sender in the drivers side head.

Problem with these sensors is QC, it sucks as they are a cheap part. The ohm specs are so tight for gauge accuracy, but the build quality can't support it.

A member on here about 5 years ago took half a dozen of them (same PN) out of their boxes on the parts counter and ohm'd them all and bought the one that would match the discrepancy in the PCM temp and what the gauge was reading, so that the gauge was actually accurate.

Re: temp gauge in dash reads low, why?

Problem with these sensors is QC, it sucks as they are a cheap part. The ohm specs are so tight for gauge accuracy, but the build quality can't support it.

A member on here about 5 years ago took half a dozen of them (same PN) out of their boxes on the parts counter and ohm'd them all and bought the one that would match the discrepancy in the PCM temp and what the gauge was reading, so that the gauge was actually accurate.

Re: temp gauge in dash reads low, why?

Have you considered an aftermarket mechanical gauge? I tested one with boiling water and it read accurately. Mine reads 190 under normal conditions which is where it should plus or minus a few degrees. The stock gauges are not meant to give a numerical reading. They are meant to give a relative reading meaning that they should be in about the same meaningless place every day, and if not, then there is likely a problem.

Re: temp gauge in dash reads low, why?

I thought about a mechanical gauge, but I wanted the one in the dash to read close to right, it wasn't, it read at about the 1/4 mark, which by looking at it is about 160ish. I put the new wells sender in last night and it works better, now it reads just above the 210 mark, I am running cold front snap ins in the grill also, may have to pull them out. The sender I got is a Wells brands part number TU230. Thanks for the help!